Lens arrangement and lens module using same

ABSTRACT

A lens arrangement includes two lenses. Each lens includes an optical portion having an optical axis, a non-optical portion surrounding the optical portion, and an engagement portion extending along the optical axis from the non-optical portion. One of the engagement portions includes an outer wall and an inner wall parallel to the outer wall with an annular groove defined therebetween, while the other engagement portion defines a corresponding annular space for receiving the outer wall and the inner wall therein, therefore the engagement portions are interferentially engaged with each other.

BACKGROUND

1. Technical Field

This present disclosure relates to lenses and, particularly, to a lensarrangement and a lens module using the lens arrangement.

2. Description of Related Art

Lens modules typically include a lens barrel and a plurality of lensesreceived within the lens barrel. At present, the lenses can beseparately held by the lens barrel directly, or can be engaged with eachother to form a lens arrangement and then held by the lens barrel. Bothof these arrangements have alignment problems, which has an impact onimaging quality.

Therefore, it is desirable to provide a lens arrangement and a lensmodule using the lens arrangement, which can overcome theabove-mentioned limitations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric, exploded view of a lens arrangement, accordingto an exemplary embodiment.

FIG. 2 is similar to FIG. 1, but showing another view of the lensarrangement of FIG. 1.

FIG. 3 is an isometric, assembled view of the lens arrangement of FIG.1.

FIG. 4 is a cross-sectional view taken along a line IV-IV of FIG. 3.

FIG. 5 is a cross-sectional view of a lens module including the lensarrangement of FIG. 1.

DETAILED DESCRIPTION

Referring to FIGS. 1-2, a lens arrangement 100, according to anexemplary embodiment, includes a first lens 10, a second lens 20 and athird lens 30.

The first lens 10, the second lens 20, and the third lens 30 can beplastic or glass lenses. In this embodiment, the first lens 10, thesecond lens 20, and the third lens 30 are plastic lenses.

The first lens 10 includes a first non-optical portion 12 surrounding afirst optical portion 11. The first optical portion 11 is configured forrefracting incident light rays and forming corresponding optical images,and defines a first optical axis 13. The first non-optical portion 12 isconfigured for engaging with the second lens 20. The first lens 10further includes a first engagement portion 14 protruding from the firstnon-optical portion 12 along and symmetrical about the first opticalaxis 13. The first engagement portion 14 is substantially annular. Thefirst engagement portion 14 includes an inner circumferential engagementsurface 14 s inclining substantially radially outwards from the firstnon-optical portion 12.

The first engagement portion 14 includes an outer wall 14 a and an innerwall 14 b substantially parallel to the outer wall 14 a. In the presentdisclosure, the outer wall 14 a and the inner wall 14 b discontinuouslyextend along a circumferential direction of the non-optical portion 12.It is noteworthy that the outer wall 14 a and the inner wall 14 b can beconfigured to continuously extend along the circumferential direction ofthe non-optical portion 12 in an alternative embodiment. An annulargroove 15 is defined between the inner wall 14 b and the outer wall 14a, configured for flexing the outer wall 14 a relative to the inner wall14 b.

The second lens 20 includes a second non-optical portion 22 surroundinga second optical portion 21. The second optical portion 21 is configuredfor refracting incident light rays and forming corresponding opticalimages, and defines a second optical axis 23. The second non-opticalportion 22 is configured for engaging with the first lens 10 and thethird lens 30.

The second lens 20 includes a first surface 20 a facing the first lens10 and a second surface 20 b opposite to the first surface 20 a.

The first surface 20 a has an extended first flange 24 and a secondengagement portion 25 protruding from the second non-optical portion 22along and symmetrical about the second optical axis 23. The first flange24 and the second engagement portion 25 both are substantially annularand parallel to each other. The second engagement portion 25 includes anouter circumferential engagement surface 25 s corresponding to the innercircumferential engagement surface 14 s. The diameter of the outercircumferential engagement surface 25 s is equal to or slightly lessthan that of the inner circumferential engagement surface 14 s.Therefore, the first lens 10 and the second lens 20 can be tightlyengaged with each other via friction between the inner circumferentialengagement surface 14 s and the outer circumferential engagement surface25 s. An annular space 26 is defined between the first flange 24 and thesecond engagement portion 25, configured for receiving the firstengagement portion 14. The inner diameter of the first flange 24 issubstantially equal to or slightly less than the outer diameter of thefirst engagement portion 14. Therefore, the first lens 10 and the secondlens 20 can be engaged with each other more efficiently andsufficiently, while the outer wall 14 a of the first engagement portion14 is slightly pressed by the second engagement portion 25.

In the present disclosure, the second surface 20 b has an extendedsecond flange 27 protruding from the second non-optical portion 22 alongand symmetrical about the second optical axis 23. The second flange 27for receiving part of the third lens 30 surrounds a receiving cavity 28.

The third lens 30 has a similar structure with the first lens 10 whichcan be engaged into the receiving cavity 28 to position the third lens30 on the second lens 20.

Furthermore, two spacer rings 40 can be correspondingly positionedbetween each of the two adjacent lenses of the first lens 10, the secondlens 20 and of the second lens 20 and the third lens 30, to avoidfriction produced therebetween.

Referring to FIGS. 3-4, upon assembly, the first engagement portion 14is received in the annular space 26 while the inner circumferentialengagement surface 14 s abuts against the outer circumferentialengagement surface 25 s. Similarly, part of the third engagement portion37 is received in the receiving cavity 28. Meanwhile, the first opticalaxis 13 is superimposed with the second optical axis 23, constituting acommon optical axis of the lens arrangement 100. As such, an alignmentof the first lens 10 and the second lens 20 is achieved.

Since the outer wall 14 a can flex relative to the inner wall 14 b, thefirst engagement portion 14 and the second engagement portion 25 can beefficiently and sufficiently deformed due to an imprecise alignment ofthe first engagement portion 14 and the second engagement portion 25,without direct deformation caused to the first imaging portion 11 andthe second imaging portion 21. Thus, the imaging quality of the lensarrangement 100 is protected from the deformations due to an imprecisealignment of the first engagement portion 14 and the second engagementportion 25.

It should be noteworthy that the lens arrangement 100 can include morethan three lenses. Each two adjacent lenses are engaged in such a waysimilar to that of the first lens 10 and the second lens 20.

Referring to FIG. 5, a lens module 200, according to an exemplaryembodiment, includes the lens arrangement 100 and a lens barrel 300. Thelens barrel 300 holds the lens arrangement 100.

While various exemplary and preferred embodiments have been described,it is to be understood that the disclosure is not limited thereto.Various modifications and similar arrangements can also be covered aswould be apparent to those skilled in the art.

Therefore, the scope of the appended claims should be accorded thebroadest interpretation so as to encompass all such modifications andsimilar arrangements.

1. A computer-implemented method of dynamically adding an applicationserver to a cluster of application servers comprising: maintaining ahistory of quality of service (QoS) for each of a plurality ofapplication servers; dynamically selecting, based on the history of QoS,an application server to add to the cluster when the cluster is under aheavy workload, the selecting, comprising broadcasting a request to theapplication servers for an application server that is able to donate anumber of processor cycles for an amount of time to the cluster torespond to the request; and dynamically adding the selected applicationserver to the cluster.
 2. (canceled)
 3. The computer-implemented methodof claim 1 wherein when two or more application servers respond to therequest within a particular time frame, the application server with amost favorable history of QoS is selected.
 4. The computer-implementedmethod of claim 3 wherein if none of the application servers thatrespond to the request has a history of QoS, the first applicationserver to respond within the particular time frame is added to thecluster.
 5. The computer-implemented method of claim 4 wherein a heavyworkload is a workload that exceeds a user-configurable threshold. 6.The computer-implemented method of claim 5 wherein when the workload nolonger exceeds the user-configurable threshold and the added applicationserver is not performing a task for the cluster, the added applicationserver is released from the cluster.
 7. The computer-implemented methodof claim 6 wherein when the added application server is released fromthe cluster, the history of QoS of the added application server isupdated.
 8. A computer program product on a tangible computer readablemedium for dynamically adding an application server to a cluster ofapplication servers comprising: code means for maintaining a history ofquality of service (QoS) for each of a plurality of application servers;code means for dynamically selecting, based on the history of QoS, anapplication server to add to the cluster when the cluster is under aheavy workload, the dynamically selecting comprising broadcasting arequest to the application servers for an application server that isable to donate a number of processor cycles for an amount of time to thecluster to respond to the request; and code means for dynamically addingthe selected application server to the cluster.
 9. (canceled)
 10. Thecomputer program product of claim 8 wherein when two or more applicationservers respond to the request within a particular time frame, theapplication server with a most favorable history of QoS is selected. 11.The computer program product of claim 10 wherein if none of theapplication servers that respond to the request has a history of QoS,the first application server to respond within the particular time frameis added to the cluster.
 12. The computer program product of claim 11wherein a heavy workload is a workload that exceeds a user-configurablethreshold.
 13. The computer program product of claim 12 wherein when theworkload no longer exceeds the user-configurable threshold and the addedapplication server is not performing a task for the cluster, the addedapplication server is released from the cluster.
 14. The computerprogram product of claim 13 wherein when the added application server isreleased from the cluster, the history of QoS of the added applicationserver is updated.
 15. A computer system for dynamically adding anapplication server to a cluster of application servers comprising: atleast one storage device for storing code data; and at least oneprocessor for processing the code data to maintain a history of qualityof service (QoS) for each of a plurality of application servers, todynamically select, based on the history of QoS, an application serverto add to the cluster when the cluster is under a heavy workload,wherein to dynamically select the application server a request is broadcasted to the application servers for an application server that is ableto donate a number of processor cycles for an amount of time to thecluster to respond to the request, and to dynamically add the selectedapplication server to the cluster.
 16. (canceled)
 17. The computersystem of claim 15 wherein when two or more application servers respondto the request within a particular time frame, the application serverwith a most favorable history of QoS is selected.
 18. The computersystem of claim 17 wherein if none of the application servers thatrespond to the request has a history of QoS, the first applicationserver to respond within the particular time frame is added to thecluster.
 19. The computer system of claim 18 wherein a heavy workload isa workload that exceeds a user-configurable threshold.
 20. The computersystem of claim 19 wherein when the workload no longer exceeds theuser-configurable threshold and the added application server is notperforming a task for the cluster, the added application server isreleased from the cluster.